1. Field
The present embodiment relates to phacoemulsification sleeves and needles and, more particularly, to combinations of sleeves and needles with features for retaining the attachment of the sleeve to the needle in a desired position during and after insertion through an incision.
2. Description of the Related Art
It is well known in the art to use a bi-axial phacoemulsification (phaco) handpiece. A phaco handpiece has a phaco needle attached to a distal end of the handpiece with a flexible irrigation sleeve surrounding most of the phaco needle and also attached to the handpiece. The sleeve typically carries irrigation fluid from an outlet in the handpiece to a surgical site. The irrigation fluid flows between the inside of the sleeve and the outside of the needle, and into a surgical site through ports formed in the sleeve. The irrigation fluid helps cool the needle during use, and also replaces fluid aspirated from the surgical site through a lumen in the needle to prevent the eye globe from collapsing during surgery. Thus the needle and sleeve provide two functions, irrigation and aspiration, in a bi-axial manner.
The irrigation sleeve is typically formed of compliant material, such as silicone or other relatively soft, compressible materials, so that the sleeve will not damage the tissue at the incision interface and also for the purpose of forming at least a partial seal at the incision to minimize fluid leaking from the eye during surgery.
Current trends in ophthalmic surgery are demanding ever smaller diameter needles and smaller incisions. It is believed that smaller incisions lead to less change in corneal curvature and better visual acuity post-operation. These smaller incisions have led to tighter interfaces with the sleeves and needles. A problem, becoming more prevalent, is that the sleeve accordions at the incision, as the surgeon attempts to insert the sleeve and needle through the incision. This problem is shown at FIG. 1. A needle 10 has passed through an incision 12 in an eye 14, but a sleeve 16 has accordioned at 18 outside the eye 14. Needle 10 is attached to a phaco handpiece 20 in a known manner, typically via a threaded connection, as shown. It is critical that sleeve 16 pass through incision 12 and into the eye 14 along with needle 10, so that sleeve 16 can protect the eye tissue from damage and to provide irrigation fluid into the eye 14.
Therefore, it would be desirable to provide a combination of an irrigation sleeve and a needle that would assist in retaining the sleeve in a desired position, as the sleeve and needle are inserted through an incision.